Yet another way in which our breasts are amazing – did you know that mothers’ breasts are the most effective way of warming a baby who is too cold? Breast skin temperature can increase by up to 2°C in just two minutes!Conversely, when they sense a baby is overheating, breast skin temperature cools to help baby cool down. Even more incredibly, the skin temperature of each breast of a mother of twins with one baby on each breast can vary between breasts if the babies have different temperatures!

​​​You have probably already heard that immediate skin-to-skin contact between mother and baby after birth is the best way to initiate breastfeeding. Indeed, research has found that babies who experience early skin-to-skin care are more likely to exclusively breastfeed at hospital discharge and to breastfeed for longer durations after discharge (Bramson 2010; Gabriel 2010; Moore 2012).

The benefits of skin-to-skin contact are not restricted to breastfeeding babies. Since 2009, based on decades of evidence, the World Health Organization and United Nations Children’s Fundhave recommended that “all healthy mothers and babies, regardless of feeding preference and method of birth, have uninterrupted skin-to-skin care beginning immediately after birth, for at least an hour”.

Beyond the first hour, the benefits of “kangaroo care”are well documented, and regulation of a baby’s temperature is just one of the benefits of kangaroo care. But keeping newborn babies warm is very important because they are not able to generate their own heat due to the lack of a shiver mechanism, which can lead to a rapid decline in temperature. When babies are cold-stressed, they use too much energy and oxygen to generate warmth: if skin temperatures drop just one degree from the ideal 97.7° F (36.5°C), a baby's oxygen use can increase by 10%. Keeping babies at optimal temperatures means they can use that energy for growing instead.

It’s easy to understand why a baby gets warm while being held by a warm human. It’s a bit harder to explain why being held by their mother, and even better by a breastfeeding mother, is even more effective at helping infants regulate their body temperature. A 2007 study confirmed earlier findings that maternal breast temperatures drop when the infant's temperature reaches 36.9° C. This does not happen with fathers performing kangaroo care; a 1992 study (Ludington-Hoe 1992) found that during the second hour of paternal kangaroo care, five out of eleven healthy preterm infants experienced skin temperatures above 37.5° C, and the trend was for infant skin temperature to continue rising as long as paternal kangaroo care continued. Although fathers can participate in kangaroo care and this can be invaluable when mothers need a break, their chests don’t prevent a baby overheating whereas those of breastfeeding mothers do. Too much clothing or heating of the room has the same inherent danger.

Furthermore, breastfeeding mothers’ breasts are more effective at warming a baby than either the baby’s father or any other caregiver who is not breastfeeding (including a non-breastfeeding mother), because milk production and mammary gland development generate considerable tissue growth and blood flow to the milk ducts, increasing breast skin temperature (Linzell 1974). Furthermore, breastfeeding mothers feel even more relaxed than other people during kangaroo care (Feldman 2002), due to the release of oxytocin (the love hormone) during breastfeeding which causes dilation of blood vessels in the breasts, further increasing breast temperature, which can miraculously be reversed when required.

The twins situation is very difficult to explain. I will just say here that there is a physiological reason why maternal breasts are able to respond differentially to each infant. If you are a scientist or a doctor and are interested in the full details (involving unmyelinated afferents, neuropeptides, pituitary thyroid axis and cutaneous corticotrophin!) you can read them just before the conclusion of the Ludington-Hoe 2007 study.

Our Mission is to help mothers worldwide to breastfeed through mother-to-mother support, encouragement, information, and education, and to promote a better understanding of breastfeeding as an important element in the healthy development of the baby and mother.